MicroRNA Expression in Rat Myocardial Infarction intervened by propranolol. Rattus norvegicus

We established a rat model of myocardial Infarction by performing a surgical operation of left anterior descending coronary artery occlusion under sterie conditions. Wistar rats were previously randomly divided into 4 groups: control, ischemia, ischemia-propranolol, and non-ischemia-propranolol. Our data suggested that propranolol could reverse many microRNAs with too high or too low expression in the ischemia group versus control group. Overall design: Wistar rats were initially anesthetized with pentobarbital (40 mg/kg, i.v.), which were previously randomly divided into 4 groups: control, ischemia (MI), ischemia-propranolol (MI-PRO), and non-ischemia-propranolol (NMI-PRO). The rat model of MI was established by performing a surgical operation of left anterior descending coronary artery occlusion under sterie conditions. Successful occlusion was confirmed by an increase in the amplitude of R wave of lead I during the first few seconds of each occlusion and elevation of S-T segment of lead II, and a 20-30% decline in the arterial blood pressure compared to the pre-ischemic values mesured by a previously installed ECG recorder (BL 420, ChengDu TME Technology Co, Ltd, ChengDu, China). Propranolol was administrated 2 months before the experiment with daily oral doses of 50 mg/kg. Hearts were quickly isolated after the rats were sacrificed and the ischemic zone of the left ventricle was prepared for the miRNA microarray experiment. Control and NMI-PRO animals underwent open chest procedures without coronary artery occlusion.